Segmentation-based super-low altitude flight control method for pilotless aircraft

Abstract

The invention discloses a segmentation-based super-low altitude flight control method for a pilotless aircraft. The method comprises the steps of: judging the flight mode of the pilotless aircraft according to a preset flight mode judging condition of the pilotless aircraft, wherein the flight mode is divided into super-low altitude flight mode, super-low altitude level-off flight mode, and super-low altitude quitting flight mode; determining the longitudinal segmented flight control strategy of the pilotless aircraft in the super-low altitude flight mode according to the judgment result, anddesigning the longitudinal segmented control law of the pilotless aircraft; and refining specific control logic and control law parameters. According to the segmentation-based super-low altitude flight control method for the pilotless aircraft, the pilotless aircraft can enters super-low altitude flight mode in a relatively stable posture under a small disturbance environment; the flight range isshortened, and the oil consumption is reduced; and after the pilotless aircraft quits the super-low altitude flight, the pilotless aircraft can climb at the maximum dynamic pressure with an allowed overload, and then enters a second super-low altitude flight or returns.

Description

technical field [0001] The invention relates to the field of unmanned aerial vehicle flight control, in particular to a subsection-based ultra-low-altitude flight control method for unmanned aerial vehicles. Background technique [0002] Ultra-low-altitude flight is a kind of tactical flight widely used in the world at present, and it has good concealment and suddenness. Ultra-low-altitude penetration tactics and technologies began during the Second World War. In the past 20 to 30 years, they have developed by leaps and bounds. , anti-tank missiles, ground attack missiles, and unmanned aerial vehicles are the most eye-catching. Applying ultra-low-altitude flight to unmanned aerial vehicles can greatly improve the concealment and maneuverability of unmanned aerial vehicles, and can achieve the greatest combat results at a relatively small cost, realizing a strategic combat style. [0003] The ultra-low-altitude flight of UAVs can conceal itself and has the incomparable supe...

AI Technical Summary

Problems solved by technology

[0004] The traditional control mode of the longitudinal channel of the UAV is to adjust the elevator rudder surface by measuring the pitch angle and the pitch angle rate to realize the UAV glide and attitude maintenance, but the height control error of this strategy is large and the mode between modes The switching is not smooth enough and the step response is large, which is not conducive to ultra-low altitude flight

At present, in response to the difficulty of ultra-low-altitude flight control of UAVs, research institutions at home and abroad mainly install laser height sensors with centimeter-level accuracy, and use the measured relative heights to directly participate in the control to improve the height control accuracy, but the cost has also increased significantly.

Some scholars have also proposed to introduce the height difference term into the UAV's ultra-low-altitude flight longitudinal control law equation to solve the problem of height overshoot. By selecting an appropriate height difference, it not only controls the rapid decline of the target drone, but also blurs the boundary between the downward and peaceful flight and achieves a smooth transition. However, this method generally adopts the PID (Proportion Integral Differential, proportional-integral-differential) method to adjust the control law coefficients, and there is still a certain overshoot, and the constant control logic throughout the process also leads to shorter voyages and higher fuel consumption.

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